1. Field of the Invention
The present invention relates to a camera having a lens opening formed at the front of a photographic lens system, in which the frontmost lens group of the photographic lens system moves along the optical axis of the photographic lens system to perform a focusing operation.
2. Description of the Related Art
In recent years, compact cameras with a built-in barrier device for opening and closing a lens opening of a camera have been generally used. As one example of such cameras, there is a camera provided with a barrier device including a barrier block mounted at the front end of a lens barrel which advances and retracts between a shooting position, (extended position) and an accommodated position in the direction of an optical axis of the photographing optical system. The barrier is closed when the lens barrel is in the accommodated position and is opened when the lens barrel is extended to the shooting position.
In the compact cameras having the barrier device described above and also a frontmost lens group in moved between an infinite focus position to a nearest focus position for a focusing operation, it is required that the lens opening and blades of the barrier device be placed at a position farther forward from the frontmost lens group so that the frontmost lens group may not touch an edge of the lens opening or the retracted barrier blades when the frontmost lens group forwardly projects for the focusing operation.
Recently, it has been strongly requested to further reduce the size of compact cameras, so much so that the space required to mount the lens opening and the barrier blades at a position further forward from the frontmost lens group in the optical axis direction must be reduced.